The present invention relates generally to ice-making machines, and more particularly to a commercial cube/crushed ice-making machine which is capable of efficiently transferring heat rejected during the ice-making process to heat water in a conventional external water supply having a conduit thereof positioned adjacent the machine.
It has long been known that there is substantial heat rejection from a condenser in a conventional refrigeration unit consisting serially of a compressor, condenser, expansion valve and evaporator. Various devices and systems have been employed in attempts to utilize the rejected heat for purposes of heating fluids such as water and air. Embodiments of specific refrigeration systems and specific heat applications therefor are disclosed in the following U.S. Pat. Nos.: 3,926,008; 4,041,726; 3,922,876; 3,358,469; 3,513,663; and 2,739,452. Further, most heretofore known commercial ice-making machines with a capacity approximating 300-1000 lbs. of ice per day have utilized air-cooled condensers, rather than more efficient water-cooled condensers, because an air-cooled condenser is cheaper and less bulky.
Recent worldwide increases in fuel and energy costs have created a need for expanding the use of heat conservation and heat reclamation systems, with specialized refrigeration systems not heretofore considered for such use.
Additionally, the prior known energy conservation systems which have been combined with refrigeration units have heretofore included controls which were responsive to changes in the temperatures of the refrigerant being cooled and the fluid being heated. While the temperature of the fluid being heated is an important parameter for control purposes, the temperature of the refrigerant in the condenser is important, but only secondarily to the efficiency of the refrigeration system. A prime factor in refrigeration efficiency is an optimum (not a maximum) pressure drop across the thermal expansion valve. None of the energy conservation systems heretofore known have disclosed a control system which optimizes the efficiency of the refrigeration unit while providing a controlled transfer of heat energy from the refrigeration condenser to an external air or water supply.
Further, it has been noted that a substantial number of commercial ice-making machines are permanently installed for use in buildings such as motels, hotels, restaurants, etc. in close proximity to external water supplies in those buildings. Applicant has realized that in certain installations a refrigerant to water condensor may be used in a commercial ice-making machine and combined with or tapped into an adjacent external water supply to provide added efficiency to the ice-making machine and, at the same time, save energy by acting as a secondary heat source for the external water supply.
Therefore, it is an object of the present invention, generally stated, to provide an refrigerating machine having improved cooling efficiency.
Another object of the present invention is to provide a new and improved refrigerating machine including heat reclamation means for heating an external water supply.
A further object of the present invention is the provision of an refrigerating machine including heat reclamation means in connection with a condenser therein and a control system for same which is responsive to a refrigerant pressure in the condenser for providing added efficiency to the refrigeration system.